The process of drilling and extracting oil is a complicated dance of hundreds of pieces of machinery. In the ancient past, oil was extracted by hand or with bamboo piping, but we’ve come a long way since then.
Among the many components of a drilling system is the figurative tip of the spear–the float shoe.
To better understand the float shoe, we need to first understand the adjacent components of an oil well.
A hole must be drilled into the earth and a casing string inserted to extract oil. A casing string is a section of long oilfield pipes lowered into a wellbore to prevent it from collapsing. Many casing strings are combined to reach the required depth. In addition, the casing string facilitates oil extraction by providing a conduit for the oil to be transported and a protective shield against the elements.
At the bottom of a casing string is a bullet-nose-shaped device called the guide shoe. The guide shoe’s shape, as its name suggests, easily guides the casing string into the wellbore. Its shape minimizes the risk of impacting rocks or other debris as the casing is lowered into the drill site.
A float shoe is an advanced type of guide shoe with an additional feature–a check valve. The check valve prevents liquids from entering the casing from the bottom, such as mud or water.
Float shoes check valves typically come in three varieties.
- Ball-type check valves use low-density balls that float in mud or cement and while floating will seal the casing.
- Often considered the most reliable variety of check valves due to fewer moving parts, like a spring.
- Spring-actuated flapper valves rely on a spring to contract under pressure and prevent backflow using a flap or lid.
- Spring-actuated poppet valves also use spring but utilize a mushroom-shaped plug to block unwanted liquid from the casing.
More Than the Sum of Its Parts
Float shoes are a vital component of modern drilling wells, but the entire assembly has to be high-quality, well maintained, and installed properly in order to work. The experts at Reddy Pipes & Supply Inc are ready to put our skills to work for you. Contact us any time to schedule a consultation.